Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: The Expression and origin of TSLP in AAA. (A) Serum TSLP concentrations patients with AAA (n=632) compared with healthy controls (n=24,036) in UKB. (B) The schematic diagram is presented below for reference. 10-12-week- aged male mice received a PPE induction at day 0, with aortic sampling performed at day 14. (C) The comparison of TSLP mRNA expression in the aortas from the sham and AAA groups at day 14 (n=6 mice per group). (D) Temporal expression profile of TSLP mRNA in the murine aorta at indicated time points after AAA induction, compared to the baseline level (n=6 mice per group). (E-G) Representative immunofluorescence images of murine AAA sections stained for TSLP (red), cell-specific markers (green), and DAPI (blue). (E) Co-staining with CD45 (leukocyte marker). (F) Co-staining with vimentin (fibroblast marker). (G) Co-staining with α-SMA (smooth muscle cell marker) (n=4 mice per group). Data are presented as mean ± SEM. Scale bar: 50 μm. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001 (the Mann–Whitney U test was used in A, unpaired two-tailed Student’s t-test was used in C, and one-way ANOVA was used in D).

Article Snippet: Exogenous TSLP treatment: Recombinant mouse TSLP protein (HY- P70626 , MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Expressing, Sampling, Comparison, Immunofluorescence, Staining, Marker, MANN-WHITNEY, Two Tailed Test

Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: Genetic ablation of TSLP receptor attenuates experiment al AAA severity. (A) Schematic of the experimental design utilizing wildtype (WT) and Tslpr − / − mice in the PPE-induced AAA model. (B) Quantification of the maximum abdominal aortic diameter in WT and Tslpr − / − mice at day 14 post-PPE induction (n=5 mice per group). (C) Representative images of elastic Elastica Van Gieson (EVG) staining of aortic tissue. (D) Elastin degradation scores evaluated by EVG staining (n=5 mice per group). (E–J) Representative immunohistochemical staining and quantitative analysis of CD68 (E, F) , MMP2 (G, H) and MMP9 (I, J) expression in the aortic wall. Positive areas are presented as a percentage of the total area (n=5 mice per group). Scale bars: (A) 1mm; (C) 100 μm (top), 50 μm (bottom); (E, G, I) 500 μm (top), 40 μm (bottom). All quantitative data are presented as mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001 (unpaired two-tailed Student’s t-test). Red arrows indicate representative positive staining areas.

Article Snippet: Exogenous TSLP treatment: Recombinant mouse TSLP protein (HY- P70626 , MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Staining, Immunohistochemical staining, Expressing, Two Tailed Test

Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: Therapeutic neutralization of TSLP protects against AAA development. (A) Schematic diagram of the experimental protocol for anti-mouse TSLP antibody (anti-TSLP) administration in the PPE-induced AAA model. (B) Comparison of the maximum abdominal aortic diameter in normal saline-treated and TSLP-treated mice at day 14 (n=6 mice per group). (C, D) Representative histological staining and corresponding quantification for Elastica Van Gieson (EVG) (n=6 mice per group). (E–J) Representative images and quantitative analysis of immunohistochemical staining for CD68 (E, F) , MMP2 (G, H) and MMP9 (I, J) expression in the aortic wall. Positive areas are presented as a percentage of the total area (n=6 mice per group). Scale bars: (A) 1mm; (C) 500 μm; (E, G, I) 200 μm (top), 50 μm (bottom). All quantitative data are presented as mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001 (unpaired two-tailed Student’s t-test). Ctrl, control. Red arrows indicate representative positive staining areas.

Article Snippet: Exogenous TSLP treatment: Recombinant mouse TSLP protein (HY- P70626 , MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Neutralization, Comparison, Saline, Staining, Immunohistochemical staining, Expressing, Two Tailed Test, Control

Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: Exogenous TSLP administration aggravates AAA in mice. (A) Schematic diagram of the experimental protocol for recombinant TSLP administration in the PPE-induced AAA model. (B) Comparison of the maximum abdominal aortic diameter in normal saline-treated and TSLP-treated mice at day 14 (n=6 mice per group). (C, D) Representative histological staining and corresponding quantification for EVG (n=6 mice per group). (E–J) Representative images and quantitative analysis of immunohistochemical staining for CD68 (E, F) , MMP2 (G, H) and MMP9 (I, J) expression in the aortic wall. Positive areas are presented as a percentage of the total area (n=6 mice per group). Scale bars: (A) 1mm; (C) 500 μm; (E, G, I) 200 μm (top), 40 μm (bottom). All quantitative data presented as mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001, ns, no significant difference (unpaired two-tailed Student’s t-test). Ctrl, control. Red arrows indicate representative positive staining areas.

Article Snippet: Exogenous TSLP treatment: Recombinant mouse TSLP protein (HY- P70626 , MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Recombinant, Comparison, Saline, Staining, Immunohistochemical staining, Expressing, Two Tailed Test, Control

Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: TSLP signaling regulates the immune microenvironment and macrophage polarization in AAA. (A, B) viSNE plots visualizing the high-dimensional CyTOF data, depicting the overall immune cell composition and the specific distribution of TSLP. (C) Quantitative analysis of the total macrophage frequency among CD11b + immune cells in the aortic tissues. (D, E) The ratio of M1 to M2 macrophages in the aortic tissues of WT and Tslpr − / − mice. (F) Gating strategy for M1 (CD86 + ) and M2 (CD206 + ) macrophages in RAW264.7 cells and BMDMs by flow cytometry. (G, H) Flow cytometry analysis and quantification of the percentages of M1 (CD86 + ) and M2 (CD206 + ) macrophages in RAW264.7 cells (G) and BMDMs (H) following polarization and TSLP treatment. (I) Proportions of M1 and M2 macrophages in PMA-differentiated THP-1 cells treated with or without TSLP. Cell stimulation conditions: M1 polarization control (Ctrl), 100ng/ml LPS + 20ng/ml IFN-γ for 24h; M1 polarization with TSLP (TSLP), 100ng/ml LPS + 20ng/ml IFN-γ+20ng/ml TSLP for 24h; M2 polarization control (Ctrl), 20ng/ml IL-4 for 24h; M2 polarization with TSLP (TSLP), 20ng/ml IL-4 + 20ng/ml TSLP for 24h (n=4–6 per group). Data are presented as mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001 (unpaired two-tailed Student’s t-test). M1, M1 macrophages; M2, M2 macrophages; DCs, dendritic cells; NK cells, natural killer cells.

Article Snippet: Exogenous TSLP treatment: Recombinant mouse TSLP protein (HY- P70626 , MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Flow Cytometry, Cell Stimulation, Control, Two Tailed Test

Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: Transcriptomic profiling reveals TSLP-mediated activation of pro-inflammatory pathways in macrophages. RAW 264.7 was stimulated with 100ng/ml LPS + 20ng/ml IFN-γ+20ng/ml TSLP (TSLP group) or 100ng/ml LPS + 20ng/ml IFN-γ for 24h (Control group) and then subjected to RNA-sequencing. (A) Principal component analysis (PCA). (B) Clustering diagram of differentially expressed gene (DEG) pattern. (C) Volcano plot displays DEGs. (D, E) Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of downregulated genes. Data are from n=4 samples per group.

Article Snippet: Exogenous TSLP treatment: Recombinant mouse TSLP protein (HY- P70626 , MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Activation Assay, Control, RNA Sequencing

Journal: Frontiers in Immunology

Article Title: Thymic stromal lymphopoietin promotes abdominal aortic aneurysm formation by regulating macrophage polarization

doi: 10.3389/fimmu.2026.1767913

Figure Lengend Snippet: Therapeutic neutralization of TSLP protects against AAA development. (A) Schematic diagram of the experimental protocol for anti-mouse TSLP antibody (anti-TSLP) administration in the PPE-induced AAA model. (B) Comparison of the maximum abdominal aortic diameter in normal saline-treated and TSLP-treated mice at day 14 (n=6 mice per group). (C, D) Representative histological staining and corresponding quantification for Elastica Van Gieson (EVG) (n=6 mice per group). (E–J) Representative images and quantitative analysis of immunohistochemical staining for CD68 (E, F) , MMP2 (G, H) and MMP9 (I, J) expression in the aortic wall. Positive areas are presented as a percentage of the total area (n=6 mice per group). Scale bars: (A) 1mm; (C) 500 μm; (E, G, I) 200 μm (top), 50 μm (bottom). All quantitative data are presented as mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001 (unpaired two-tailed Student’s t-test). Ctrl, control. Red arrows indicate representative positive staining areas.

Article Snippet: Anti-TSLP antibody treatment: Anti-TSLP antibody (HY-P990150, MCE, USA) was administered via intraperitoneal injection starting on day 1 after PPE induction at a dose of 20 mg/kg, and then every other day thereafter.

Techniques: Neutralization, Comparison, Saline, Staining, Immunohistochemical staining, Expressing, Two Tailed Test, Control